Selena Gomez knows just how to please her main squeeze Justin Bieber. Take his much younger brother and sister to her Hotel Transylvania premiere! But keep track of their shoes.

Over the weekend, Gomez took Bieber’s siblings Jaxon and Jazmyn to the Toronto International Film Festival premiere of her fun, musical, vampire girl-falls-for-human dude animated comedy romance, featuring Gomez as 118-year-old teen vamp Mavis, Andy Samberg as backpacking boy-crush Jonathan, Adam Sandler as Mavis’ overly protective pop Dracula, and a slew of others, including Steve Buscemi and Fran Drescher.

What were Jaxon and Jazmyn’s take on the film?

“They loved it. They enjoyed it. We lost some shoes, and they got really excited, but it was good,” Gomez, grinning, told EW.com at a press junket for the movie on Sunday.

“That’s a good quote for the movie. ‘The movie’s so good you’ll lose your shoes!’” said Saturday Night Live alum Samberg, seated with Gomez at the junket. The pair giggled together.

In the movie, Mavis rocks a blunt-banged indie girl look and is stuck in her dad’s monsters-only hotel. Dad is uptight, and hates humans. Life surges into wackiness, with a dash of puppy, er, vampire love, when Jonathan shows up, sounding like a Berkeley, Calif. Phish-loving hippie.

Gomez said she had fun recording her parts, separate from Samberg doing his, and that she was “kind of just myself,” not needing to change her naturally deep, fairly husky voice. “I was by myself, but luckily I got to hear what he had recorded previously, so I could kind of play off of what he had done,” said Gomez.

“Adam came in a few of the sessions, just to watch over, and it was good.”

She also sang a few lines in the movie, in a blow-out number at the very end.

Samberg called Gomez’ voice “perfect.” “You didn’t need to change anything … I thought Mavis was one of the best characters,” he gushed.

“Awww,” responded Gomez.

As for Samberg, wearing big nerdy glasses and a plaid shirt, his California roots, like, totally played a part voicing Jonathan. “It was definitely kind of a bro voice. There’s a little Northern and Southern Cali,” said Samberg, born and raised in Berkeley.

When asked about a very VERY different sort of movie she’s in, Harmony Korine’s totally wild, skin-and-sex filled Spring Breakers, which also premiered at Toronto, Gomez responded, “Uh oh.” (Jaxon and Jazmyn, do not see this movie until you’re older!).

“It’s intense,” she said. “You have to understand Harmony’s way of working too. I’m really proud of it. It’s great. It’s been fun. I like kind of switching it up. They’re both films that I’m really really proud of, and very different.”

Joking (or not?), Samberg dead-panned, “We’re both just killing it. We’re multi-talented, like, singers, and actors. We put out albums, and we’re in movies, but we’re also on TV sometimes. … The sky is the limit for the two of us, and that’s what’s so great, especially you.” He turned to Gomez, cracking up, adding, “Because [pause] you can sing.”